The DOI matches its Crossref record; 39 of the 39 references it cites were found in a registry or an index.
Metronomic Photodynamic Therapy as a New Paradigm for Photodynamic Therapy: Rationale and Preclinical Evaluation of Technical Feasibility for Treating Malignant Brain Tumors¶
Abstract
The concept of metronomic photodynamic therapy (mPDT) is presented, in which both the photosensitizer and light are delivered continuously at low rates for extended periods of time to increase selective tumor cell kill through apoptosis. The focus of the present preclinical study is on mPDT treatment of malignant brain tumors, in which selectivity tumor cell killing versus damage to normal brain is critical. Previous studies have shown that low-dose PDT using 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) can induce apoptosis in tumor cells without causing necrosis in either tumor or normal brain tissue or apoptosis in the latter. On the basis of the levels of apoptosis achieved and model calculations of brain tumor growth rates, metronomic delivery or multiple PDT treatments, such as hyperfractionation, are likely required to produce enough tumor cell kill to be an effective therapy. In vitro studies confirm that ALA-mPDT induces a higher incidence of apoptotic (terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate, sodium salt nick-end labeling positive) cells as compared with an acute, high-dose regimen (ALA-aPDT). In vivo, mPDT poses two substantial technical challenges: extended delivery of ALA and implantation of devices for extended light delivery while allowing unencumbered movement. In rat models, ALA administration via the drinking water has been accomplished at very high doses (up to 10 times therapeutic dose) for up to 10 days, and ex vivo spectrofluorimetry of tumor (9L gliosarcoma) and normal brain demonstrates a 3-4 fold increase in the tumor-to-brain ratio of PpIX concentration, without evidence of toxicity. After mPDT treatment, histological staining reveals extensive apoptosis within the tumor periphery and surrounding microinvading colonies that is not evident in normal brain or tumor before treatment. Prototype light sources and delivery devices were found to be practical, either using a laser diode or light-emitting diode (LED) coupled to an implanted optical fiber in the rat model or a directly implanted LED using a rabbit model. The combined delivery of both drug and light during an extended period, without compromising survival of the animals, is demonstrated. Preliminary evidence of selective apoptosis of tumor under these conditions is presented.
Overview
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
In the citing paper
“The dose of ALA and light as well as the light dose (fluence) rate may also determine how cells die of PDT, with low-dose PDT often inducing apoptosis and high-dose PDT typically resulting in necrosis [32,33].”
From 5-Aminolevulinic Acid as a Theranostic Agent for Tumor Fluorescence Imaging and Photodynamic Therapy (2023) · cites this paper as [32]
Citations
Cites
Browder, T. D., Butterfield, C., Kräling, B. M., Shi, B., Marshall, B., OʼReilly, M., & Folkman, J. (2000) · PubMed · Cited by 1,543
Kennedy (1992) · doi:10.1016/1011-1344(92)85108-7 · Cited by 1,166
Stummer, W., Novotny, A., Stepp, H., Goetz, C., Bise, K., & Reulen, H. J. (2000) · Journal of Neurosurgery · doi:10.3171/jns.2000.93.6.1003 · Cited by 881
Less is more, regularly: metronomic dosing of cytotoxic drugs can target tumor angiogenesis in mice
Hanahan, D., Bergers, G., & Bergsland, E. K. (2000) · Journal of Clinical Investigation · doi:10.1172/jci9872 · Cited by 868
Barth, R. F. (1998) · Journal of Neuro-Oncology · doi:10.1023/a:1005805203044 · Cited by 358
Antiangiogenic treatment enhances photodynamic therapy responsiveness in a mouse mammary carcinoma.
Ferrario, A., von Tiehl, K., Rucker, N., Schwarz, M. A., Gill, P. S., & Gomer, C. J. (2000) · PubMed · Cited by 253
Henderson, B. W., Busch, T. M., Vaughan, L. A., Frawley, N. P., Babich, D., Sosa, T. A., Zollo, J. D., Dee, A. S., Cooper, M. T., Bellnier, D. A., et al. (2000) · PubMed · Cited by 248
Patterson, M. S., Wilson, B. C., & Graff, R. (1990) · Photochemistry and Photobiology · doi:10.1111/j.1751-1097.1990.tb01720.x · Cited by 198
Self-citationKerbel, R. S., Klement, G. L., Pritchard, K. I., & Kamen, B. A. (2002) · Annals of Oncology · doi:10.1093/annonc/mdf093 · Cited by 177
Transport of 5-aminolevulinic acid between blood and brain
Ennis, S. R., Novotny, A., Xiang, J., Shakui, P., Masada, T., Stummer, W., Smith, D. E., & Keep, R. F. (2003) · Brain Research · doi:10.1016/s0006-8993(02)03749-6 · Cited by 146
Research works printed but not linked: 4
- Henderson, 2000, Cancer Res, 60, 525
- Browder, 2000, Cancer Res, 60, 1878
- Ferrario, 2000, Cancer Res, 60, 4066
- Madsen, 2000, Photochem. Photobiol, 72, 128, 10.1562/0031-8655(2000)072<0128:PTOHGS>2.0.CO;2 · DOI
Cited by
Sorted by citations
Imaging and Photodynamic Therapy: Mechanisms, Monitoring, and Optimization
Celli, J. P., Spring, B. Q., Rizvi, I., Evans, C. L., Samkoe, K. S., Verma, S., Pogue, B. W., & Hasan, T. G. (2010) · Chemical Reviews · doi:10.1021/cr900300p · Cited by 2,359
The physics, biophysics and technology of photodynamic therapy
Wilson, B. C., & Patterson, M. S. (2008) · Physics in Medicine and Biology · doi:10.1088/0031-9155/53/9/r01 · Cited by 1,043
Self-citationA Review of Progress in Clinical Photodynamic Therapy
Huang, Z. W. (2005) · Technology in Cancer Research & Treatment · doi:10.1177/153303460500400308 · Cited by 912
Oncologic photodynamic therapy photosensitizers: A clinical review
Allison, R. R., & Sibata, C. H. (2010) · Photodiagnosis and Photodynamic Therapy · doi:10.1016/j.pdpdt.2010.02.001 · Cited by 840
Photodynamic Therapy—Current Limitations and Novel Approaches
Günaydın, G., Gedik, M. E., & Ayan, S. (2021) · Frontiers in Chemistry · doi:10.3389/fchem.2021.691697 · Cited by 628
Metadata
- Authors
- Bisland, S. K., Lilge, L., Lin, A., Rusnov, R., & Wilson, B. C.
- Affiliations
- University Health Network (CA)
- Venue
- Photochemistry and Photobiology
- Publisher
- Wiley
- Published
- 2004
- Volume
- 80
- Issue
- 1
- Pages
- 22
- ISSN
- 0031-8655 (ISSN-L)
- OpenAlex
- W2065744257
- Cited by
- 173
- References
- 39
- Citations by year
- 2025: 1 · 2024: 8 · 2023: 10 · 2022: 5 · 2021: 7 · 2020: 12 · 2019: 7 · 2018: 7 · 2017: 4 · 2016: 10 · 2015: 5 · 2014: 16 · 2013: 4 · 2012: 7
- FWCI
- 8.68
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Photochemistry and Photobiology (publishedVersion)
- PubMed (publishedVersion)
- BioOne Complete (BioOne) (submittedVersion)
- Funders
- National Cancer Institute (P01 CA43892, P01CA043892)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Cancer Research › Photodynamic Therapy Research Studies
- Physical Sciences › Engineering › Biomedical Engineering › Nanoplatforms for cancer theranostics
- Health Sciences › Medicine › Oncology › Glioma Diagnosis and Treatment
- Keywords
- malignant brain tumors, 5-aminolevulinic acid, protoporphyrin IX, apoptosis, hyperfractionated radiotherapy, 9L gliosarcoma, tumor growth modeling, fluorescence spectroscopy
- MeSH terms
- Brain Neoplasms, Clinical Trials as Topic, Humans, Photochemotherapy, Apoptosis
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review